This invention relates to improvements in yard hydrants.
The yard hydrant conventionally includes a discharge nozzle above ground level connected to a standpipe or riser that extends into the ground below the frost line to well known working parts connected to a source of water supply under pressure. When water flow is turned off, residual water within the hydrant is subject to freezing at freezing temperatures and to avoid such freezing, a common expedient has been to provide a drain hole below the frost line so the water will drain out into the surrounding ground. A disadvantage with such a drain hole is the fact that it is also a means for reentry of water into the hydrant which intermixes with other water passing therethrough so that under such conditions, there is the possibility of contamination of the hydrant water from impure seepage which, if it occurs, can result in deleterious effects upon the user and very likely be in violation of rules and regulations relating to water sanitation. Accordingly, in the hydrant art, structures have been developed which eliminate the drain hole and substitute some form of a storage reservoir whereby the residual water can be contained and subsequently discharged above ground level. It is with improvements in such a reservoir component that this invention is concerned.
With some of such structures, the reservoir is constructed within the riser pipe which must, of necessity, be of a large enough diameter to accommodate the reservoir components that exceeds the diameter of conventional standard size pipe sufficient for the hydrant water flow purposes, and in other forms, the reservoir is an entirely separate unit requiring additional separate flow connections to the riser pipe. With both arrangements, there are required components that add to rather than reduce the overall cost of the product, and thus, in an industry where there is a constant search for lower cost alternatives and where minor reductions in costs can become a formidable and valuable asset when mass production is involved as it is in this field, these present type of hydrant reservoir constructions have the disadvantage of not being cost effective for enhancing the marketability and sale of the finished product.
With the above observations in mind, it is one of the important objects of this invention to provide a yard hydrant with a separate sealed water reservoir built around a standard size standpipe or riser.
Another object herein is to provide a reservoir as characterized that is isolated from the water system pressure of the hydrant.
A further object is to provide a reservoir of the above class that includes a deformable diaphragm for enlarging a water storage area.
Still another object is to provide a yard hydrant reservoir into which water left in the hydrant flow line when the flow is shut off is transferred directly into the reservoir without danger of pollution.
A further object is to provide a yard hydrant as characterized in which substantially all of the stored water is expelled through the nozzle when the hydrant is turned on.
Another object is to provide a hydrant of the above class in which internal parts within the riser can be quickly and easily withdrawn for repairs or servicing.
Another object is to provide a hydrant as characterized that affords economies in manufacture for its intended purpose.